Tree watering question (irrigation, landscaping, grow, trees)

[HB2HSV]

I've always assume a slow drip is beter than a garen hose pouring for 5~10 minutes, but this morning I bgean to ask myself...

Why?

If I slow drip, say at a rate of 1 gallon per hour, as oppose of simply pour 1 gallon of water at the base of tree. Since the soil around tree is loose, wouldn't 1 gallon of water drain deeper and faster? Wouldn't the root benefits this better than the slow drip, which may cause shallow root problem?

As background, where I live the clay soil is very compact so the water does not drain fast. When I dig a hole for a tree (1 inch trunk), I'd dig a 1 foot deep and 3~4 feet diameter hole. I then amend the clay soil with peat moss, humus, mushroom compost and organic soil conditioner. So the soil around the tree is loose but outside of 3~4 feet diameter the clay is very compact.

[Omaha Rocks]

When I plant trees (3 Autumn Blaze Maples this year - each about 3" trunk & 18' tall) I tie a plastic 5-gallon loosely to the tree. I drill a 1/8" hole on one edge of the bottom of the bucket. I fill the 5-gallon bucket once or twice per day and let it drip slowly.

The main reason I do this is because the slow-drip allows the water to drain down instead of just running out.

I don't know that this would work ideally in all situations, or in all areas. But it seems to work for me.

[Shagbark Hickory]

Really best if you don't ammend your soil with your compacted clay situation. You've been digging nice wide planting holes and that's fantastic. That's all you need to do. Contrary to popular belief trees do grow in clay soil. Ammending the soil in for a new tree just give the roots a reason to wrap around the tree rather than forge onward.

And as the Omaha rocks said, with clay soil you have to water a little just to get it receptive to more water so it doesn't run off. If you've amended your planting hole this really isn't an issue but you can always just stick a finger in the soil about 3" deep BEFORE and AFTER you water and see what's going on. You will want to keep an eye out for girdling roots.

[Shagbark Hickory]

When compacted clay soil is ammended like that, water can collect in the planting hole. It may appear to drain on the surface but it's not draining out in the clay.
This can lead to root rot.
Most trees don't like "wet feet".

Another reason to water slow.

[no kudzu]

Not adding ammendants to clay soil is relatively new thinking- 30 years ago we were all taught to amend soil for everyting we plant but trials have shown it really doesn't help that much so digging a wide hole is the best bet. However- IMO ammending the soil for vegetable and ornamental plantings is quite necessary. Most perennials and annuals really respond to ammended soil. It is best to till the entire bed with added organic material but many times I just get impatient and only ammend the hole I'm planting in. I plant my perennials much more close than recommended to keep the weeds at bay so eventually each bed ends up completely ammended anyway.
My favorite is Natures Helper which is simply ground pine bark and mushroom compost. and a product usually used for roses called Mills Magic Mix. A bed with Mills Magic Mix eventually makes the soil so very rich and the drainage is great. When you put your shovel in it feels lilke sugar. I usually have to order on line and in large quantities as I can't find it in stores.

Alot of folks don't realize that the feeder roots of trees are in the first 6 inches of the soil. I knew a man who thought he had to water deep enough to reach the tap root. He didn;t believe me when I told him the tap root only held the tree in place and didn't tap into anything but soil. So yes you can drown a newly planted tree by adding ammendments when planting and then over watering and this usually happens when you water too fast.

[Shagbark Hickory]

Originally Posted by no kudzu

Not adding ammendants to clay soil is relatively new thinking- 30 years ago we were all taught to amend soil for everyting we plant but trials have shown it really doesn't help that much so digging a wide hole is the best bet. However- IMO ammending the soil for vegetable and ornamental plantings is quite necessary.

Yes you're right about that. Similar to pruning sealer and staking, ammending soil for planting trees has really fallen out of favor. I would also agree about amending soil for vegies and flowers. That's OK. But on trees it's not a good practice.

[HB2HSV]

Originally Posted by Shagbark Hickory

When compacted clay soil is ammended like that, water can collect in the planting hole. It may appear to drain on the surface but it's not draining out in the clay.
This can lead to root rot.
Most trees don't like "wet feet".

Another reason to water slow.

So if it rains hard (like it's doing today) all my trees will have "wet feet"?

[no kudzu]

yep

[Shagbark Hickory]

Originally Posted by HB2HSV

So if it rains hard (like it's doing today) all my trees will have "wet feet"?

They have "wet feet" when water collects in the planting hole. The clay does not drain quickly so it forms a "bowl" filled with water there where your container mix and ammended soil is.

So if "all of your trees" are planted in this fashion with ammended soil on top of clay soil that does not drain very well then these planting holes could have rain water collecting in them which to most trees, is not tolerated.

Some trees do tolerate standing water for extended periods. Sweetgum, Bald cypress, black gum, and swamp white oak are a few that come to mind. But like I said most ornamentals want moist but well draining soil and can suffer in wet conditions.

[Art123]

Originally Posted by Shagbark Hickory

They have "wet feet" when water collects in the planting hole. The clay does not drain quickly so it forms a "bowl" filled with water there where your container mix and ammended soil is.

So if "all of your trees" are planted in this fashion with ammended soil on top of clay soil that does not drain very well then these planting holes could have rain water collecting in them which to most trees, is not tolerated.

Some trees do tolerate standing water for extended periods. Sweetgum, Bald cypress, black gum, and swamp white oak are a few that come to mind. But like I said most ornamentals want moist but well draining soil and can suffer in wet conditions.

Excellent responses Shagbark!

While working in landscaping, I once pulled out nearly an entire backyard landscape that was dead. Each plant was planted in clay with highly amended soil immediately around the plant. Basically they were all sitting in little "pots" with no drainage hole! The homeowner was soaking the beds with an irrigation system that filled each one of these "pots" with water. As we pulled up each dead plant, we could see a couple inches of water in the bottom of each hole. The roots were rotted. It was an expensive mistake. We spent an entire day with a whole crew tilling in and amending all the beds with a 10-20% mix of compost and conditioner as deep as possible. Then, we replanted the whole thing (with new plants obviously).